Villarreal were rewarded for a stellar defensive showing as a goalless draw against Bayer Leverkusen was enough for them to progress to the Europa League quarter-finals.
Marcelino's side travelled to the BayArena for Thursday's second leg with a 2-0 lead thanks to Cedric Bakambu's double in the first contest at El Madrigal.
And a resolute Villarreal rear guard protected that advantage brilliantly to frustrate a Leverkusen side that failed to show a clinical edge in front of goal.
The visitors were happy to sit back and allow Leverkusen possession in the first half, while Villarreal midfielder Denis Suarez missed a great opportunity.
Marlon Frey fired over in the penalty area on the stroke of half-time for the hosts, before Kyriakos Papadopoulos hit the crossbar early in the second half.
Leverkusen continued to control possession in the second period, but Villarreal almost caught the hosts cold with Cedric Bakambu, Roberto Soldado and Manu Trigueros going close, the latter seeing a stoppage-time effort hacked off the line.
Those missed chances mattered little, though, as Villarreal saw out the match to put their name in the draw for the last eight.
The opening 20 minutes proved a war of attrition with Leverkusen probing, but Sergio Asenjo - playing his first match in 11 months due to a serious knee injury - was untested in the Villarreal goal.
Hakan Calhanoglu saw tentative penalty appeals waved away by referee Willie Collum after claiming he was unfairly felled by Asenjo.
Leverkusen continued to put pressure on the visitors' defence and Javier Hernandez went agonisingly close to meeting Karim Bellarabi's dangerous right-wing centre.
The hosts were almost undone on the counter-attack when Soldado broke free and found Suarez in the area, but his first touch was heavy and Bernd Leno was out quick to make the save.
Leverkusen had chances either side of half-time to make the breakthrough. First, Frey blazed over from close range when the ball fell kindly to him from a Calhanoglu corner, before Christoph Kramer curled wide of the far post from the left of the area.
Roger Schmidt's men went even closer in the 54th minute when Papadopoulos headed Calhanoglu's corner into the ground and saw the ball bounce agonisingly off the bar.
Leverkusen's desire to commit men forward left them exposed to the counter and Bakambu perhaps should have done better when he drilled wide after Suarez's cross deflected into his path off Jonathan Tah.
Leno then came to the hosts' rescue with a brilliant one-handed save from Soldado's point-blank header.
Calhanoglu brought the best out of Asenjo with a well-hit low drive in the closing stages as Leverkusen continued to be frustrated, and Trigueros was only denied a winner for Villarreal in injury time by Andre Ramalho's incredible block on the line.